Method of making burglar-alarms.



F. J. WILKES.

METHOD 0F MAKING BURGLAR ALARMS.

APPLICATION FILED DEC.26, |9144 Patented May 16, 1916.

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miran erf-lilas PATENT onirica.

FREDERIC-K d'. WILKES', OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO DELIA M.

VVILKES. l

METHOD OF MAKING BURGLAR-ALARNS.

Specification of Letters Patent.

Patented May 16, 1916.

To all 'w hom it may conce/rn ,Be it known that l, Fnnornrcii J. lViLirns, a citizen of the United States, und a resident of the city of Philadelphia, county of Phila.

i whether lowering the upper, or raising the lower, sash, and upon the latter regardless of whether it swings to the right or left.

Another object is to provide an alarm operative to fire a blank cartridge or detonat- 1n r ca b means ofas rin actuated hame P y P g mer, released by a door or sash. operated trigger, the spring engaging only the rear end of said hammer and operating in alinement with the longitudinal axis thereof.

Still another` object of the invention is to provide A a method of manufacture of an alarm, which accomplishes all of the bene- -ficial results of those previously placed on the market, but cuts the cost of production down' to a relatively small fraction of that formerly experienced.

Heretofore, in the design and manufacture f alarms of this character it has been customary in general to provide a casting, which requires a considerable amount of machining, drilling, finishing, etc., and then is susceptible of being more or less easily broken or cracked (particularly when made of cast iron).

This invention, however, relates to the formation of the body portion of an alarm, comprising the base, cartridge support, plunger or hammer guide, and spring casing, from a one-piece metal punching, pressed into final shape by dies and with but two opzrations. Furthermore, aside from the fact hat sheet metal punchings are much less ex- )ensive than castings in general and particuarly 'so in this case, the finished device is nuch less liable to break when in the process f manufacture, while being shipped from lace to place, and when in use on being subjected to the sudden and severe shocks to which thelsarne must from the very nature of its service and operation be subjected.

Further details as to the advantages and construction of the invention are fully brought out in the following specification in which- Figure 1 is a front elevation of the invention 1n its preferred embodiment as applied to the frame of a door-way; Fig. 2 is a similar view showing the relative positions of the parts of the device after having operated upon the opening of the door; Fig. 3 is a Vertical sectional view of the device in operative position; Fig. 11 is a top plan view of the same; Fig. 5 is a section on the line 5-5 of Fig. 3; Fig. 6 is a plan View of the blank from which the 'casing is formedg-and Fig. 7 is a view showing the application of the device to an ordinary window sash.

Referring to the drawings, a door 10 is shown in Fig. 1 as closed and substantially filling the door-way or frame 11, to which latter is secured the device forming the subject of the present invention. In Fig. 2, the device is shown as having been operated by the opening of the door, thereby giving an audible signal or alarm by exploding the cartridge or .detonating cap provided for this purpose.

The alarm device comprises a metal plate or punching such as that shown in Fig. 6, folded and bent in such manner as to form parallel, overlapping base portions 12 and 13, one being extended to form ears 14, through which screws or other fastening means pass tol maintain the device in a given position upon the desired object. Said base portions are bent upwardly and inwardly until they meet, whence they together form a support l5 for the outwardly extending substantially 'cylindrical looped portions 16, 17 and 18, these respectively comprising the spring casing,-hammer guide and a cartridge support. The spring easing 16 is closed at its upper end by means of radially inwardly bent V-shaped ears 19, while its lower end is open and separated from the hammer guide only by the transversely extending slot 20, in which oscillates the pin or trigger 21 of the hammer 22, provided in turn with a firing point 23.

-Within the cylindrical support 18 Vis placed a cartridge or the like 25, pointing downwardly and prevented from slipping either' of these members,

therethrough by the. coiperatioi'i of the flange Q6 with the upper ede-e portion of the former.- l'Vhcn set in py tion to `operate, the respective parts of the device are as shown in Fig. l wirA the trinu `r intended laterally into the path of the door, or window sash. Obviously, then, any opening of throws said trigger around until the spring 3() is Vableto force thelihainnier through thcguide'l?, as said trigger approaches the slanting part 3l 0f the slot leading into the longitudinally eX- tending slot Thereupon, the hammer is projected violently through its guide by virtue of the coiled spring, until the movementofthe i'iringpoint 23 is arrested by enga'geinentwith the priming 4cap of the cartridge', this impact being more thanv suficient to explode the charge Within the cartridge` shell. From this position, the device is reset byv forcing` the trigger back through the"slot2 until it reaches Athe transverse slot-.20, lwhence itv is oscillated to one 4side or the other.

.fis shown Fig. ,7, the embodiment of the invention as described above, may be readily applied to a window, to give an alarm when Vthe saine is opened after the device has been set. Preferably the alarm is'secured upon the. upper face of the lower side of the upper 'sash frame 36, and-when' set with the trigger llextending laterally into the path o fthe lower' sash 37. "Consequently, upon either lowering the'upper,`or raising the lower sash', the valarm cartridge is explodedin the manner hereinbefore described.

l'hus, I-have provided a. burglar alarrn which entirely fulfils all the requirements my hand this burglar alarm, which consists in pressing a metal blank to form a complete loop, the

portions of said blank adjacent tosaid loop.

being'brought together to form a supporting shank, thence being bent laterally outwardly in opposite directions, and one por.l tion then being bentreversely one to overlapV the other, ,to form a rigidv base `comprising three thicknesses of metal substantially throughout its transverse extent. r

2.' The method of making a casing for-a.l burglar alarm, which conslstsin pressing a metal blank to form aV complete loop,the

portio'nsof said blank adjacentto said loop being brought together to form a supporting.

shank, thence being bent laterally outwardly in opposite directions, andr one edge portion then being bent reversely to. overlap the other reverselybent edge portion, 'to grip Qsaid'second edge portlon and prevent sepa,-

ration of th'e'sides of said Supporting shank,

and to forma rigid base of three thicknesses.

In witness whereof, I have hereunto set HERMAN F. GRUNINGER, EDWARD J. OKEEFE.

19th of December,Y AnD., 

